Electromechanical switching device

ABSTRACT

The invention relates to a electromechanical switching device having two movable contact elements interacting with a fixed contact. Said switching device has a housing. When viewing a fixing side from the top, said housing is divided into two areas bordering with a longitudinal side of the housing, one of the movable contact elements and the corresponding fixed contact being located in said areas, wherein each of the housing areas has a narrow partial area and a broad partial area bordering therewith. The broad partial area of the first housing area is adjacent to the narrow partial area of the second housing area and the narrow partial area of the first housing area is adjacent to the broad partial area of the second housing area. The actuation directions of the movable contact elements are directed opposite each other.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the US National Stage of International ApplicationNo. PCT/EP2004/003536, filed Apr. 2, 2004 and claims the benefitthereof. The International Application claims the benefits of Europeanapplication No. 03009941.0, filed Apr. 30, 2003, both applications areincorporated by reference herein in their entirety.

FIELD OF INVENTION

The invention relates to a electromechanical switching device,especially an electromagnetic switching device, having at least twomovable contact elements interacting with a fixed contact, which arearranged in adjacent areas of a housing subdivided into a number ofareas.

SUMMARY OF THE INVENTION

An electromagnetic switching device with a divided housing, in whichsubareas each switch one current track, is for example known from DE 3242 062 C2. Electromagnetic actuators as well as a thermal actuator arearranged in a first part of the housing featuring a first contact point.A second contact point and a further electromagnetic actuator arearranged in the second part of the housing. In addition there is an arcsplitter chamber in each part of the housing. The switching mechanismsin the two parts of the housing are coupled. There is no provision for athermal actuator, i.e. one that responds after a delay, in the secondpart of the housing.

Whereas the dividing surface between the two areas of the housing in theswitching device known from DE 32 42 062 C2 runs in parallel to onefixing side of the housing, such a dividing surface within a housing ofa switching device can for example also run perpendicular to the fixingplane in other embodiments. In each case, where there is provision forinstalling a larger number of individual components compared to aswitching device with an undivided housing of the corresponding size,the result is restricted fitting space which typically requires themanufacturing of relatively expensive to manufacture and/or to installspecial components, for example coils with non-round cross sections.

A circuit arrangement with two housing parts is known from EP 0505 292A1, in which a central dividing wall features an offset in a smallcentral section in order in this way to create space in one of thehousing parts for a thermal bimetallic element.

The object of the invention is to specify an electromechanical,especially an electromagnetic switching device with at least two movablecontacts as well as fixed contacts interacting with these, which with arational construction features an especially compact housing subdividedinto a number of areas.

In accordance with the invention this object is achieved by the claims.In this case two movable contacts as well as fixed contacts interactingwith these are arranged in a housing which is essential divided along animaginary dividing surface which is perpendicular to a fixing side ofthe housing. By contrast with conventional multipart housings howeverthe dividing surface within the housing preferably features a sideoffset, in approximately the center of the housing, so that each of thetwo parts of the housing feature a broader area and a narrower areaadjoining it. In this case the narrow area of the second housing partadjoins the broad area of the first housing part and vice versa.

The mounting position of the two circuit arrangements comprising amovable contact and a fixed contact in the housing in each case can becharacterized by the direction of operation of the relevant movablecontact, in which said contact meets its assigned fixed contact or fixedcontacts during the switching process. Preferably the actuationdirections of the movable contacts are in opposite directions to oneanother. This enables circuit arrangements which do not have a uniformwidth all the way along to be accommodated in the housing in anespecially space-saving way, said arrangements for example beingnarrower in an area adjoining the fixed contact than in an areaadjoining the movable contact. Opposing actuation directions of themovable contacts are not taken exclusively to mean cases in which theangle between the actuation directions amounts to exactly 180°, but alsocases in which the angle has any other value of more than 90°.Alternatively however embodiments are also implemented in which thedirections of actuation of the movable contacts are at leastapproximately the same.

Preferably the two housing areas are identically formed, but aremirrored around a geometrical vertical axis in the housing, i.e. in eachplane they are thus centrosymmetric in relation to the geometricalvertical axis.

Especially suitable is the design of the housing for a switching devicewhich contains two actuators with an immediate response, especiallyelectromagnetic actuators, as well as two actuators with a delayedresponse, especially thermal actuators. Preferably this type ofswitching device is employed as a circuit breaker.

Thus, in this preferred embodiment an electromechanical switching devicewith two actuators which respond immediately and two actuators with adelayed response, with a housing with one fixing side and longitudinalhousing sides arranged perpendicular to this is produced, whereby in afirst area of the housing adjoining the first longitudinal side of thehousing the first actuator which responds immediately of the firsttransverse housing side faces the first actuator which responds after adelay of the second transverse housing side and in a second housingareas adjoining the second longitudinal housing side the second actuatorwhich responds after a delay of the first transverse housing side facesthe second actuator which responds immediately of the second transversehousing side.

Typically the minimum width of a circuit breaker is determined by thedimensions of the electromagnetic actuator as well as an arc splitterchamber where necessary. To accommodate a number of electromagneticactuators within a standardized housing of a series device, especiallywith a width of 18 mm, some of the coils used in the prior art employeda cross section which deviated from the circular form. The manufactureof such coils, especially with a long, almost rectangular cross-section,is however relatively expensive compared to the manufacture of coilswith a circular cross-section. In addition coils with a circularcross-section are as a rule better as regards their energy efficiency.The inventive arrangement of the actuators in the switching deviceallows simple use of actuators manufactured using conventional roundcoils, which each have a width of at least, preferably more than, halfthe total width of the housing. The same also applies to the arcsplitter chambers arranged for each contact point.

An especially compact design of the housing can advantageously beachieved by the directions of actuation of the striker pins in the coilsof the actuators being opposed to each other. The directions ofactuation of the striker pins are in this case identical to thedirections of actuation of the assigned movable contacts, preferably atleast almost identical. In this way it is possible for the coil of oneactuator in the housing to be adjacent to the striker pin of the otheractuator in each case, which is very small by comparison with it. Bycomparison with the electromagnetic actuators the delayed actuators,which are also preferably embodied as bimetal strip actuators arerelatively narrow.

Relative to an axis disposed normally to the housing fixing side thecircuit arrangement of second immediate-response and seconddelayed-response actuator is essentially rotated through 180° relativeto the circuit arrangement of first immediate-response and seconddelayed-response actuator. The particular advantage of the restricted oropposite arrangement of the individual actuators in the housing lies inthe fact that even if each of the two circuit arrangements does notfeature both an immediate-response and a delayed-response actuator, theindividual components generating heat, especially coil and bimetalelements, are distributed evenly over the housing which is compactoverall. Furthermore only small amounts of heat are produced because ofthe short current paths in the switching device.

A number of exemplary embodiments of the invention are explained ingreater detail below on the basis of a drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a and b show in symbolic cross-sectional diagrams anelectromechanical switching device with two movable contacts able to beactuated in opposite directions,

FIGS. 2 a and b show a schematic diagram of the division of a switchingdevice into a number of housing areas in each case,

FIGS. 3 a and b show greatly simplified cross-sectional diagrams of aswitching device with a housing divided up lengthwise,

FIGS. 4 a and b show an incomplete perspective diagram of a circuitbreaker as an electromechanical switching device with a housing shell oran indicated housing,

FIG. 5 shows a perspective diagram of a part of the switching deviceaccording to FIGS. 4 a and 4 b, and

FIGS. 6 a and b show a cross-sectional diagram of a switching deviceaccording to FIGS. 4 a and 4 b in each case.

Parts which correspond to each other or operate in the same way areshown by the same reference symbols in all the Figures.

DETAILED DESCRIPTION OF INVENTION

FIGS. 1 a and 1 b show symbolically in lengthwise section or crosssection an electromechanical switching device 1 as a series built-indevice in which two current paths are switched. To this end switchingdevice 1 features a housing 8, which is subdivided lengthwise into afirst housing area 18 and a second housing area 19. In each of thehousing areas 18,19, for switching a current path there is a movablecontact element 33,34 and a fixed contact 35,36 which interacts with itin each case. The first movable contact 33 arranged in the first housingarea 18 is movable in a direction of actuation R1 in the direction ofthe assigned first fixed contact 35, while the second movable contact 34in the second housing area 19 is movable in the opposite direction ofactuation R2 to close the corresponding current path to the second fixedcontact 36. The movable contacts 33,34 are for example able to beactuated manually or electromagnetically. As regards further possibledetails of the switching device 1 the reader is referred to thedescription given for FIGS. 4 a to 6 b.

FIGS. 2 a and 2 b show different variants of the cross section of thedesign of a switching device 1. In the exemplary embodiment according toFIG. 2 a the two housing areas 18,19 are formed in an identical way butare mirrored around a geometrical vertical axis A in the housing 8. Thewidth B of the housing 8 is 18 mm, also referred to as one pitch unit(TE). The housing 8 according to FIG. 2 b by contrast has a width of twopitch units (TE). In this case the individual housing areas 18,19 areeach present twice in the housing 8. The form of a housing area 19 iscreated in each case by rotating an adjacent housing area 18 by 180°.

FIGS. 3 a and 3 b show a symbolic circuit breaker as switching device 1.An immediate-release actuator 2, 3 and a delayed-release actuator 4, 5are arranged in the housing area 18,19 in each case. A compartment 37 isshown between the two actuators. Furthermore there is an arc splitterchamber 6, 7 in each of the two housing areas 18,19. The layout and thefunction of the mirrored circuit arrangements, each with animmediate-release actuator 2,3 and a delayed-release actuator 4,5 areidentical. The switching device 1 with this layout is also referred toas a 1+1 device. The pairs of contacts each with one movable contact33,34 and one fixed contact 35,36 are not shown in FIGS. 3 a and 3 b.

The circuit arrangements in the housing areas 18,19 are not necessarilyidentical. If for example in one of the housing areas 18,19 there isonly one pair of contacts, but not a delayed or immediate actuator, nora splitter system, the switching device is referred to as a 1+N switch.The stated components, namely an immediate-release actuator 2,3, adelayed-release actuator 4,5, an arc splitter chamber 6,7, as well as apair of contacts comprising a movable contact 33,34 and a fixed contact35,36 in one of the housing areas 18,19, and only one pair of contactsin the other housing area 18,19, are for example also contained in aso-called LS+HS switch, meaning a combination of circuit breaker andauxiliary circuit switch.

If the two housing areas 18,19 each contain exclusively one pair ofcontacts, but none of the previously-mentioned other components arepresent, this switch is a built-in (EBS) switch. Furthermore there isthe option for example of combining the components of a circuit breaker1 within one of the housing areas 18,19, as shown in FIG. 3 b, with justone pair of contacts and a delayed-release actuator 4,5 in the secondhousing area 18,19, i.e. of not providing an immediate-release actuatorand an splitter system in one of the housing areas 19. Furthercombinations within a switching device 1 are also implemented, dependingon specific requirements.

FIGS. 4 a to 6 b show detailed diagrams of an exemplary embodiment of acircuit breaker 1 as an electromechanical switching device with twoelectromagnetic actuators 2,3, thermal actuators 4,5 and arc splitterchambers 6,7 in each case. A switching mechanism interacting with theactuators 2,3,4,5 is not shown for reasons of clarity. A housing 8 ofthe switching device 1 is composed of two housing halves 9,10 and has awidth B. On a fixing side 11 the housing 8 features a cutout 12 whichallows it to be attached to a support bar known as a top-hat bar in theknown way. The sides of the housing perpendicular to the fixing side 11are referred to as the transverse sides 13,14 and lengthwise sides15,16. Two terminals 17 in each case are accessible from the transversesides 13,14. Thus two current paths exist in each case, from a terminal17 of the first transverse housing side 13 to a terminal 17 of thesecond transverse housing side 14. The current paths lead through onehousing area 18,19 in each case, which is delimited by the firstlengthwise housing side 15 or the second lengthwise housing side 16.Each of the housing areas 18,19 features a broad partial housing area20,21 and a narrow partial housing area 22, 23, whereby the broadpartial housing area 20 of the first housing area 18 adjoins the narrowpartial housing area 23 of the second housing area 19 and the broadpartial housing area 21 of the second housing area 19 adjoins the narrowpartial housing area 22 of the first housing area 18. Between thehousing areas 18,19 a dividing wall 24 can be seen which features anangled section 25 which defined the transition from the broad partialhousing areas 20,21 to the narrow partial housing areas 22,23.

In the broad partial housing areas 20,21 a number of deionizing plates26 of an arch splitter chamber 6,7 in each case are located between theelectromagnetic or immediate-release actuator 2,3 and fixing side 11.

Through the middle of the angled section 25 of the dividing wall 24 runsan imaginary vertical axis A, which is arranged as a normal axis to thefixing side 11 and intersects any mounting rail present approximately inthe middle. The electromagnetic actuators 2,3 as well as the thermal ordelayed-release actuators 4,5 and the arc splitter chambers 6,7 are eacharranged at least approximately symmetrically to vertical axis A. Thesame applies to the contact pieces—not shown—arranged between anelectromagnetic actuator 2,3 and an associated thermal actuator 4,5 ineach case, especially the movable contacts. The electromagneticactuators 2,3 each feature a coil 29,30, within which a striker pin31,32 is guided, for which the direction of actuation is specified by R1or R2. Part of each pin 31,32 is adjacent to the coil 30,29 of the otherelectromagnetic actuators 3,2 in each case and is provided for actuatinga latching mechanism not shown with which the thermal actuators 4,5 alsointeract.

Each of the coils 29,30 has a width b which is also equivalent overallto the width of the electromagnetic actuators 2,3, and, as can beespecially seen from FIGS. 3 a and 3 b, is greater than half of thewidth B of the housing 8. The width B preferably amounts to 18 mm, alsoreferred to as a unit of pitch with standard series built-in devices.Within this pitch unit one phase conductor and one neutral conductor ortwo phase conductors can be switched within the switching device 1 forexample. The almost even distribution of components which generate heat,especially the actuators 2,3,4,5 within the housing 8 means that despiteits compact dimensions, the housing guarantees a high switchingcapability. Likewise the space for the arc splitter chamber 6,7 is verywell utilized. Furthermore there is no mutual magnetic influence betweencoils 29, 30, which are spaced far apart by comparison with coilsarranged alongside each other. The coils 29,30 are rationallymanufactured with circular wire.

1. An electromechanical switching device, comprising: two fixedcontacts, two movable contact elements each configured to interact withthe fixed contacts; and a housing comprising a mounting side, whereinthe housing viewed from above the mounting side is subdivided into firstand second housing areas each adjoining a lengthwise side of thehousing, wherein one of the movable contact elements and the associatedfixed contact are located in each housing area, each housing area havinga narrow partial housing area and an adjoining broad partial housingarea, wherein the broad partial housing area of the first housing areais arranged adjacent to the narrow partial housing area of the secondhousing area, and the narrow partial housing area of the first housingarea is arranged adjacent to the broad partial housing area of thesecond housing area, wherein the two movable contact elements arearranged and configured to be respectively actuated by a first actuationforce and a second actuation force, the first and second actuationforces having opposing directions.
 2. The switching device in accordancewith claim 1, wherein the two housing areas are formed in an identicalway but are mirrored around a geometrical vertical axis in the housing.3. The switching device in accordance with claim 1, wherein at least onehousing area contains an immediate-release actuator.
 4. The switchingdevice in accordance with claim 2, wherein at least one housing areacontains an immediate-release actuator.
 5. The switching device inaccordance with claim 3, wherein a width of the immediate-releaseactuator is at least as large as half of a width of the housing.
 6. Theswitching device in accordance with claim 4, wherein a width of theimmediate-release actuator is at least as large as half of a width ofthe housing.
 7. The switching device in accordance with claim 3, whereinthe immediate-release actuator comprises a coil with a roundcross-section.
 8. The switching device in accordance with claim 5,wherein the immediate-release actuator comprises a coil with a roundcross-section.
 9. The switching device in accordance with claim 1,wherein at least one housing area contains a delayed-release actuator.10. The switching device in accordance with claim 2, wherein at leastone housing area contains a delayed-release actuator.
 11. The switchingdevice in accordance with claim 3, wherein at least one housing areacontains a delayed-release actuator.
 12. The switching device inaccordance with claim 5, wherein at least one housing area contains adelayed-release actuator.
 13. The switching device in accordance withclaim 7, wherein at least one housing area contains a delayed-releaseactuator.
 14. The switching device in accordance with claim 1, whereinthe housing comprises more than two housing areas.
 15. The switchingdevice in accordance with claim 2, wherein the housing comprises morethan two housing areas.
 16. The switching device in accordance withclaim 3, wherein the housing comprises more than two housing areas. 17.The switching device in accordance with claim 1, wherein the housingareas contain different circuit arrangements.
 18. The switching devicein accordance with claim 2, wherein the housing areas contain dilThrentcircuit arrangements.
 19. The switching device in accordance with claim3, wherein the housing areas contain different circuit arrangements.